package com.maibow.util;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class DESUtil {
    public final static String DES_KEY = "DJJD3|SS88dsakljdsjk%%~``++jdlkjaslkd290-9&8$";

    Key key;

    public DESUtil() {

    }

    public DESUtil(String str) {
        setKey(str); // 生成密匙
    }

    public Key getKey() {
        return key;
    }

    public void setKey(Key key) {
        this.key = key;
    }

    /**
     * 根据参数生成 KEY
     */
    public void setKey(String strKey) {
        try {
            KeyGenerator _generator = KeyGenerator.getInstance("DES");
            _generator.init(new SecureRandom(strKey.getBytes()));
            this.key = _generator.generateKey();
            _generator = null;
        } catch (Exception e) {
            throw new RuntimeException("Error initializing SqlMap class. Cause: " + e);
        }
    }

    /**
     * 加密 String 明文输入 ,String 密文输出
     */
    public String encryptStr(String strMing) {
        byte[] byteMi = null;
        byte[] byteMing = null;
        String strMi = "";
        BASE64Encoder base64en = new BASE64Encoder();
        try {
            byteMing = strMing.getBytes("UTF8");
            byteMi = this.encryptByte(byteMing);
            strMi = base64en.encode(byteMi);
        } catch (Exception e) {
            throw new RuntimeException("Error initializing SqlMap class. Cause: " + e);
        } finally {
            base64en = null;
            byteMing = null;
            byteMi = null;
        }
        return strMi;
    }

    /**
     * 解密 以 String 密文输入 ,String 明文输出
     *
     * @param strMi
     * @return
     */
    public String decryptStr(String strMi) {
        BASE64Decoder base64De = new BASE64Decoder();
        byte[] byteMing = null;
        byte[] byteMi = null;
        String strMing = "";
        try {
            byteMi = base64De.decodeBuffer(strMi);
            byteMing = this.decryptByte(byteMi);
            strMing = new String(byteMing, "UTF8");
        } catch (Exception e) {
            return null;
        } finally {
            base64De = null;
            byteMing = null;
            byteMi = null;
        }
        return strMing;
    }

    /**
     * 加密以 byte[] 明文输入 ,byte[] 密文输出
     *
     * @param byteS
     * @return
     */
    private byte[] encryptByte(byte[] byteS) {
        byte[] byteFina = null;
        Cipher cipher;
        try {
            cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.ENCRYPT_MODE, key);
            byteFina = cipher.doFinal(byteS);
        } catch (Exception e) {
            throw new RuntimeException("Error initializing SqlMap class. Cause: " + e);
        } finally {
            cipher = null;
        }
        return byteFina;
    }

    /**
     * 解密以 byte[] 密文输入 , 以 byte[] 明文输出
     *
     * @param byteD
     * @return
     */
    private byte[] decryptByte(byte[] byteD) {
        Cipher cipher;
        byte[] byteFina = null;
        try {
            cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.DECRYPT_MODE, key);
            byteFina = cipher.doFinal(byteD);
        } catch (Exception e) {
            throw new RuntimeException("Error initializing SqlMap class. Cause: " + e);
        } finally {
            cipher = null;
        }
        return byteFina;
    }

    /**
     * 文件 file 进行加密并保存目标文件 destFile 中
     *
     * @param file
     *            要加密的文件 如 c:/test/srcFile.txt
     * @param destFile
     *            加密后存放的文件名 如 c:/ 加密后文件 .txt
     */
    public void encryptFile(String file, String destFile) throws Exception {
        Cipher cipher = Cipher.getInstance("DES");
        // cipher.init(Cipher.ENCRYPT_MODE,
        // getKey());
        cipher.init(Cipher.ENCRYPT_MODE, this.key);
        InputStream is = new FileInputStream(file);
        OutputStream out = new FileOutputStream(destFile);
        CipherInputStream cis = new CipherInputStream(is, cipher);
        byte[] buffer = new byte[1024];
        int r;
        while ((r = cis.read(buffer)) > 0) {
            out.write(buffer, 0, r);
        }
        cis.close();
        is.close();
        out.close();
    }

    /**
     * 文件采用 DES 算法解密文件
     *
     * @param file
     *            已加密的文件 如 c:/ 加密后文件 .txt *
     * @param destFile
     *            解密后存放的文件名 如 c:/ test/ 解密后文件 .txt
     */
    public void decryptFile(String file, String dest) throws Exception {
        Cipher cipher = Cipher.getInstance("DES");
        cipher.init(Cipher.DECRYPT_MODE, this.key);
        InputStream is = new FileInputStream(file);
        OutputStream out = new FileOutputStream(dest);
        CipherOutputStream cos = new CipherOutputStream(out, cipher);
        byte[] buffer = new byte[1024];
        int r;
        while ((r = is.read(buffer)) >= 0) {
            cos.write(buffer, 0, r);
        }
        cos.close();
        out.close();
        is.close();
    }

    public static void main(String[] args) throws Exception {
        /*DESUtil des = new DESUtil("DJJASDKL888dsakljdsjk%%~``++jdlkjaslkd290-9&8$");
        // DES 加密文件
        // des.encryptFile("G:/test.doc",
        // "G:/ 加密 test.doc");
        // DES 解密文件
        // des.decryptFile("G:/ 加密 test.doc",
        // "G:/ 解密 test.doc");
        String str1 = "201507082032264624fc39a2";
        // DES 加密字符串
        String str2 = des.encryptStr(str1);
        // DES 解密字符串
        DESUtil des1 = new DESUtil("DJJASDKL888dsakljdsjk%%~``++jdlkjaslkd290-9&8$");

        String deStr = des1.decryptStr(str2);
        StringBuilder sb = new StringBuilder();

        System.out.println(" 加密前： " + str1);
        System.out.println(" 加密后： " + str2);
        System.out.println(" 解密后： " + deStr);
        
        String desStr = des1.decryptStr("jk/ih1KLbtNEK7iJhgEoEDIzkRu1v+PT9zcGWlgx6Z0=");
        System.out.println(" 解密后---： " + desStr);*/
        String str = "/Td6WFoAAATm1rRGAgAhARYAAAB0L+Wj4AFRAQVdABGICqfJeJWaXR0sjwRpdS7E"
                        +"+6IpZ7jEgwnjNXF1I+Am53CER4uNimC3eWr2cLkUF4wS790hhcFJDPibD3E6vykU"
                        +"wfVcZtkxf49xh2iethSwFIx3fmnT/Qzol3c2NzHNLm08op6oj6c6IymXQoTGUfjt"
                        +"QMm4Q8yuiGCX2iLAqUsg/SFnJNb1G4QuOWCVZSQwrNnHoZnAsJjXKdxW82xVSI5H"
                        +"T2GH19HrQWj7mAIv2hEG7rHr7Lvc5KrtVPN4+jGZQPbvWM4Mh+Sjx/wTyxQ14MW/"
                        +"FgSVKDir3PXIfM3/4bPggO6EQc3KOgNzQl+E5ePAoI0wNh+KEohXqYVt4giRNm52"
                        +"ypAgAAAAAAC8TejHH4hG6QABoQLSAgAAiuAM5LHEZ/sCAAAAAARZWg==";
        DESUtil des = new DESUtil();
        String desStr = des.decryptStr(str);
        System.out.println(" 解密后---： " + desStr);
    }
}